Four-wheel rear-drive chassis



M. M. BROCKWAY Nov. 22, 1927 I FOURWHEEL REAR DRIVE CHASSIS 2 Sheets-Sheet 1 Filed Dec. 22, 1525 0 if JNKENTOR 4 0 Nov. 22, 1927.

. M. M. BROCKWAY FOUR-WHEEL REAR DRIVE CHASSIS Filed Dec. 22, 1926 2 Sheets-Sheet 2 service brakes may supported on the Patented Nov, 22, 1927.

PATENT. OFFICE.

MUBILLO M. BBOCKWAY, OE FFZIRBANK; CALIFORNIA.-

roun-wunnr. REAB-DBIVE bHASSIS Application This invention relates to chassis of the type employing dirigibly mounted wheels at one end and two pairs other end for effecting Therehave been a six-wheel type of chassis proposed, some of them being in use. Some of these s 1x wheel chassis. have but two of the wheels driven, whereas others have four wheels drlven. course, this latter type is to be preferred because of the greater efie'cti ve tractive effort that can be exerted. More or .less difiiculty drivin'g'of the chassis.

' is experienced in constructing a four-wheel drive chassis because each pair of drive wheels must be so mounted as to be free to 1 move vertically with respect to the other pair of drive wheels, since the chassis does not run along a plane surface at all times but the drive wheels must accommodate themselves to-the grades and inequalities ofthe roadways.

An object of the invention is simplicity of construction as compared with many prioi known four-wheel drive slx-wheel 9 chassis.

An advantage of the invention is that V be employed on all four drive wheels and, besides, brake may be provided on the drive shaft.

By my construction I have succeeded in utilizing the shaft drive for therear pair of drive wheels without the necessity of positioning the rear drive shaft at a comparatively great angle, as is necessary when a difi'erential is mounted on each set of drive axles.

Another advantage of my combination is that there is economy of power because of elimination of one of the unsprung axles commonly found in chassis utilizing the four-wheel rear drive principle.

By this invention I am on bled to secure the advantages of the Hotcnkiss type of drive and the type employing radius rods.

Bv this invention I am enabled to minimize the unsprung weight since two of the differentials and one of the drive shafts are chassis frame, which, of course is spring-supported in the usual or any eferred manner.

By my construction, it is unnecessary that the axles of the two pairs of drive wheels of drivewheels at the large number of the type of leading pair of drive wheels which are an emergency driving P area December 22, 1926'. Serial ms. "156,460.

be linked together with radius rods or solid connections, thus permitting free and independent action of each zfxle unit around independent center's.

My invention permits of the use ofa solid non-rotating axle for the front or mounted upon bearings supported by said axle. This gives sufficient clearance so. that the rear axle drive shaft can extend ap-' proximately horizontally over said front A further advantage of this construction is the reduction in the number of universal 'oints required. 1

Another advantage is that the brake rods for operating the brakes of one pair of drive wheels work upon a center that'is independent of the center. for the brake rods for operating the brakes of the other pair of drive wheels.

By my construction I secure equal load distribution on the axles of thedrive wheels.

The brake on the drive shaft, in my construction, is applied ahead of the differential that connects the two pairs of drive wheels, thereby giving equal braking upon all four drive wheels with said brake. The accompanying drawings illustrate the invention.

. Figure 1 is a side elevation of a chassis constructed in accordance with the provi-' 810113 of this lnvention,

the neardrive wheels being omitted.

Figure 2 is a plan view of the rear portion of the chassis, omitting a portion of the chassis frame.

Figure 3 is an elevation of Figure 2:, artly in section, from the irregular line indicated by 3. -3, Fig. 2.

Figure 4 is an enlarged side elevation of the forward gear train and fragments of the shafts connected thereby.

Figure 5 is an enlarged sectional elevation on-the line indicated by 5-'5. Fig. l.

Figure-(dis a plan view of the rear gear train, the case therefor being shown partly in section. V

Figure .7 is an enlarged sectional elevation on the line indicated by 7-7, Fig. 4.

Figure 8 is an enlarged tion on the line indicated by '8-.-8,-Fig. 6.

sectional eleva- Figure 9 is an enlarged sectional detail taken on the line indicated by 99, Figure 1. n v

Figure 10 is an enlarged sectional detail taken on the line 10-10, Figure l.

The chassis frame indicated at 5, and one end thereof is supported in the usual manner on dirigible wheels, only one of which can be seen at 6 in Fig.1 because of the nature of the view. Near the other end of the frame 5 are spaced spring supports 7, 8, the support 7 being a solid, non-rotating a-xle upon which are mounted vehicle springs 9, and the support 8 being a housets 27 are mounted on the outer mg for the rear axles, and on the su ort 8 are mounted vehicle springs 10. Eac hvehicle spring 9 is connected at its forward end by a shackle 82 to a bracket 83 which is connected with the chassis frame 5 and each of said springs 9 is connected at its rear end by a shackle 13 to a backet 14 that is connected with the chassis frame. To each bracket 14 is pivoted at 15 the forward end of one of the vehicle springs 10, 'and'each vehicle spring 10 is connectedat its rear end by a shackle 16 to a bracket 17 which is connected with the chassis frame. This provides for the rear set of vehicle springs 10, a form of spring suspension used with the Hotchkiss type of drive. It is tobe understood, however, that the shackles may be omitted and radius rods employed in a manner well understood in this art.-

Preferably, fixed to the chassisframe but are pivotally connected thereto and to accomplish this there are rovided outside of the frame 5 and exten ing longitudinally'thereof rock members 74 which are secured in any suitable 'manner to the. brackets 14. Each bracket 14 has abearing 79 through which extends a stub shaft 76 secured by a key 77 and screw 78 to a bracket 84. The brackets '84 are riveted or otherwise secured to the frame 5. To retain the brackets 14 on the stub shafts-76,'nuts 81 are screwed onto the outer ends of saidstub shafts, there being preferably washers-80 between the nuts 81 and thebearings 79. The brackets-'17, 83 are secured to the opposite ends of the members 74.; From this it will be readily understood that the members 74 are free to rock about the axes of the shafts 76 when either pair of driven wheels meets with an uneven traction surface of such amplitude that compression or/and expansion of the springs. 9 or/and 10 will not sufiice.

Within the housing 8 are axles 18- which connect at their outer ends to the rear drive wheels 19 that are rotatably mounted, in a manner well understood in this art, on tubular end portions of ner ends of the exles 18 connect with difl'erential gearing A within the housing 8 and this gearing, in turn, is driven through any is sectional and the'housing 8. The in' gearingA is connected by a unlversal joint 22 to adrive shaft- 23.- This drive shaft 23 by a universal joint 231.

Rotatably mounted on the axle 7 in a manner well understood in this art are forward or leading'drive wheels 24 and connected With each drive wheel 24 is a sprocket 25. Each sprocket 25 is connected by a sprocket chain 26 with a sprocket -27 and the sprockends of jackshafts 28 rotatably supported at said outer ends. in bearings 29, 30. The bearings 29- 30 are supported by a tubular housing 31 tat surrounds the jack-shafts. The 11 secured to the frame 5. Loose] 0n the end portions of the housing, 31 are collars 302 which are connected by'radius rods 303 to the rear brake flanges 304. The" the sections are connected I ousing"31} is supported near its ends by brackets 301 y mounted 1 shown, in a manner well understood in this art. The shaft 33 is in sections connected the brackets/14, '17 are not b of gearing connecting the shafts 23, 28, 33

y a universal joint 331. Thoughthe train may be of any suitable construction: that will answer my purpose, said train, in this and the shaft- 39 turns in bearings 42 also The spider 35, in I mounted in the case 32. this instance, may be driven at different speeds at any gears 43, 44, of different sizes. 45, 46, on a slidably mounted sleeve'47,may be selectively engaged with the respective gears 43, 44. The sleeve 47, in thecustomary manner of sleeves of this character, is splined the case'32, and the sleeve'47 is shifted by a fork 50operated by a rod-51 which extends to within reach of the driver.

The shaft 48 is driven by a spur gear 52.

mounted thereon in mesh with a spur gear 53 which is mounted' 'on the shaft 33. In the case 32 is a bearing 54 fcr the shaft 33.

gear 37 given speedof the shaft 33, i and, for this purpose, is provided with spur Spur gears ,on a shaft 48'that rotates in bearings 49 in The shaft 39 is provided at its forward end with a bevel pinion 5.5 which meshes with a bevel gear 56 rotatably mounted in bearings 57 carried by the case 32.

The bevel gear 56 is cated in general by the character 58. {In

' the spider 561 are rotatably mounted bevel pinions 59 which ,meshwith bevel gears 60 fixed to the inner ends of the respective shafts 28.

Though any suitable type of diflerential gearing A may be employed, that shown in detail inFigures 6 and 8 is constructed as follows:

The innerends of the axles 18 are provided with bevel gears 61 which mesh with bevel pinions 62 carried by a spider 63. The I spider 63 rotates in bearings 64' in the housing 8. The spider 63 has on its periphery a spur gear 66, whereby the differential gearing is driven.

I gear 661 is 111 mesh with a spur pinion .67

'mounted on a shaft 68 that turns in bearings 69 in the housin'g'S.

The shaft 68 is driven by a bevel gear 70 mountedthereon in mesh pinion 71 fixed to the rear end of the shaft 21.,

If desired, a brake 72' may v e to the shaft 33 as well as brakesifd'f several wheels, -19, 24. r

The invention operates as follows of the vehicle thus drivin fl fthe ear 56 which,

. 58' through the differential gearing 58. vThe any other reason,

shafts 28 transmit power to the wheels 24:.

It will'be seen that the differential gearing 58 is driven through-the difierential gearing 34 and that'said difierential gearing 34 also effects driving of the shaft 23 which, in turn,

drives the shaft 21. Turning of the shaft 21 operates the shafts 18 through the gear train that includes the differential gearing Therefore, that all of the power 'drivenfiwheels 19, 2 1, can act independently when the chassis is being steered ina curved path, or when, for one or more of the wheels should be'dr'iven at a higher speed than the a fact that'the differential gearings others and that, because of my new combination oflcertain features of construction, the unsprungweight is minimized due to the 34, 58 and the shaft the shaft 33, aswell as a portion of I 23,- are supported on the chassis frame which,

of course, is supported by the springs 9, 10.

- It will be clear that, by my construction, it is not necessary to link together the two pairs of drive 'wheels with radius rods,

springs or solid connectionsas in many prior four-wheel drive 'six and eight-wheel chassis formed on the spider 561 of differential gearing which is indi- Vaxles, differential gearing last-mentioned wheels,

In this instance, the spur with; a; .bevel rotating axle,

"supported and in part on the housing,-jack shafts rotat- 1 ably mounted on the frame and connected by The shaft 33 Wlll be driven by the'rn'o'tonwdrive the sprockets 27 and thus;

ferential gearing,

differentialgearing, and means driven by the L ferential gearings, from the foregomg 1t-w111 be clear tioned differential said third differentlal gearing, and means driven by the third differential gearing to acter described comprising a frame,

axles, a non-rotating axle,

a frame,

mounted on the last-mentioned axle, resilient supports housing and between the frame and non-robetween the frame and.

tating'axle, sprockets connected with the a v jack. shafts, on the jack shafts, chains connecting the first and, second mentioned sprockets, a housmg for the jack shafts supportedbyfhe frame,

a case secured to the last mentioned housing,

differential gearing Imounted inythe case a third difand connecting the jack shafts, ferential gearing connected with the first and second mentioned differential gearings, and means to operate i-thej third differential gearing.

2. A four-wheel drive chassis of the character described comprising a frame, three differential. gearings, axles connected by one of. the/differential gearnrgs, a housing for sprockets said axles, wheels secured to the axles, a nonwheels rotatably mounted on the last mentioned axle, a frame yieldingly in part on the non-rotating axle a second one of the Y differential gearings, chain and sprocket connections between the jack shafts and the last mentioned. wheels, means driven by a third one ofthe differential gearingsto drive the first mentioned difmeans to drive said third third differential gearing to drive the second differential gearing. v v

3. A four-wheel drive chassis of the character described comprisin threedifferential gearings, axles connected by one of the difa housing for said axles, wheels "secured to the axles, a non-rotating axle, wheelsrotatably mounted on the last mentioned axle, a fram e,*rock members pivotallyconnected-with the frame and yieldingly supported in part on the non-rotating axle and in part on the housing, jack Shafts rotatably mounted on the frame and connectedbya second one of the differential gearings, charm and sprocket connections between the ack shafts and the last mentioned wheels,; means driven by a third one of the differential gearings to drive the first mengearing, means to drive drive the second differential gearing;

4:. A four-wheel drive chassis of the charrock members pivotally connected with the frame. yielding means supporting the opposite ends of the rock members, a wheel supporting each spring, a diflerential gearing connect' ing two of the wheels j ;ick shafts rotatably mounted on the frame, a second differential gearing connecting said jack shafts, driving connections between the jack shafts and the other two Wheels, a third difi'erential gearing, mea ns driven by the third difierential 1o gearing to drive the first mentioned differential gearing, means todrive the third difof Nov. 1926.

MURILLO M. BROCKWAY; 

